Most strains of the E. coli bacterium are harmless, while others can cause severe symptoms across both healthy and vulnerable populations, causing symptoms of abdominal pain, nausea, fatigue, and dehydration. Sources of E. coli contamination can vary, including raw or undercooked food, unclean drinking water, and physical contact with an infected.
A current E. coli outbreak in Flathead County, Montana, confirmed to have been caused by contaminated meat products, has resulted in 14 hospitalizations and one death so far. In France, a 2022 E. coli incident led to the deaths of two children, dozens of illnesses, and a lawsuit against food giant Nestle.
While the impact of those deaths and number of people sickened can never be minimized, the ease at which E. coli can spread offers an unfortunate opportunity to affect even larger groups of people. Today, Food Poisoning News takes a look at the deadliest and second largest E. coli outbreak ever recorded.
In the spring and summer of 2011, Germany experienced one of the most severe food-borne illness outbreaks in recent history. The incident, caused by a rare strain of Escherichia coli (E. coli) known as O104:H4, affected thousands and resulted in 50 deaths.
The outbreak began slowly, with only 138 cases reported by mid-May. However, by the end of the month, the number of confirmed cases in Germany had risen to 373, with additional cases reported in other European Union countries. The peak of the outbreak occurred in mid-June, with thousands affected.
The German health authorities reported that about 900 patients developed hemolytic uremic syndrome (HUS), a potentially life-threatening condition that can lead to kidney failure. The majority of cases were centered around Hamburg in northern Germany, though some cases were reported in other European countries among individuals who had recently visited Germany.
Scientists identified the source of the infections as E. coli O104:H4, a strain that combines characteristics of both enterohemorrhagic E. coli (EHEC) and enteroaggregative E. coli (EAEC). Researchers at the University of Maryland School of Medicine found that this strain possessed a unique combination of virulent factors, making it particularly dangerous.
As health authorities worked to contain the outbreak, an investigation was launched to identify the source of contamination. Initially, Spanish cucumbers were suspected, leading to their removal from store shelves. However, this lead was quickly disproven but not before significantly impacting the economy.
Attention then turned to bean sprouts produced at a farm in northern Germany, but tests on sprouts from the suspected farm came back negative for O104:H4.
The breakthrough in the investigation came in late June when French health officials reported a small cluster of HUS cases near Bordeaux, linked to the consumption of various sprouts, including fenugreek, mustard, and arugula. Genetic testing confirmed that the same O104:H4 strain was responsible for both the French and German outbreaks.
A European Food and Safety Authority (EFSA task force traced the source to a single lot of fenugreek seeds that were mported from Egypt by a German distributor in November 2009. The seeds were then sold to approximately 70 companies, with more than 50 of them in Germany. In response, European authorities removed suspected Egyptian seeds from the market and implemented a temporary ban on the import of fenugreek seeds from Egypt to Europe.
Egyptian officials countered by asserting that E. coli could not survive for two years on dried seeds. They suggested that contamination likely occurred due to improper handling by the distributor or the use of contaminated water by growers.
The outbreak was declared over on July 26, 2011, after a three-week period passed without any new reported cases. In total, the outbreak affected 4,321 people and claimed 50 lives, making it the deadliest E. coli outbreak on record.
This incident led to increased scrutiny of food safety practices and heightened awareness of the potential for new, highly virulent pathogens to emerge in the food supply chain. It also prompted discussions about improving traceability mechanisms and international cooperation in disease surveillance and investigation.
The economic impact of the outbreak was significant, particularly for the Spanish agriculture industry, which suffered losses estimated at nearly $300 million due to the initial, incorrect implication of Spanish cucumbers as the source.
As a result of this outbreak, health authorities worldwide have updated their protocols for responding to food-borne illness outbreaks and have focused on the importance of rapid, accurate identification of contamination sources.
Commenting on this story, one national E. coli lawyer said, “Widespread outbreaks of foodborne illness can lead to significant financial losses due to medical expenses, lost productivity, and wasted food. Effective food safety measures and stringent enforcement by regulatory agencies helps to minimize these costs and maximize public health.”
